This newly completed interdisciplinary doctoral research undertaken at the Centre for Textile Conservation and Technical Art History, University of Glasgow, built up the first complete picture of textile dyeing techniques in the Ming and Qing Dynasties (1368-1911), China, which not only significantly contributed to textile history, but is also very helpful for the better understanding, exhibition and preservation of historical and archaeological textiles of this time period.
During the Ming and Qing Dynasties in China, imperial textile handicrafts reached its production peak. However, little was known about dyeing techniques in this time period except for few isolated studies on dye recipes or dyestuffs on textiles. This doctoral research set out an unprecedented comprehensive investigation of dyeing techniques of the Ming and Qing Dynasties, by combining the archival research of documented dye recipes, the chemical analysis of dyestuffs on historical and archaeological textiles, as well as art historical, botanical and colour studies.
Innovative chemical and botanical research on traditional Chinese dyestuffs
Fundamental research on the chemical characterisation of reference dyestuffs and their botanical provenance was undertaken for accurate understanding of the dyestuffs and robust identification of dye sources. Ultra-high performance liquid chromatography coupled with Photodiode array detector and Mass spectrometer (UHPLC-PDA-MS), and three different extraction methods were first applied to dyed silk samples prepared with 22 individual reference dyestuffs to separate and identify their characteristic components. The first database of the chemical profiles of dyestuffs in ancient China was established. Moreover, the esterification and isomerisation patterns of the dye constituents of gallnut, gardenia and saffron, and the dye composition of acorn cup dyed silk were clarified for the first time, which helps better identification of dye sources containing tannins and crocins (Fig. 2). 6-Hydroxyrubiadin and its glycosides were unprecedentedly reported on a dyed sample with Rubia cordifolia from China, which contributes to the provenance of different Rubia species as dye sources in Asia. Additionally, ethnographic dyed samples and dyestuffs from Li group in south China were chemically studied as modern references and compared with the above results, marking the start of the chemical research of ethnographic dyeing in China.
Another major innovation was integrating research from botany and Chinese herbal medicine with research into dyeing properties to provide botanical provenance for the dyestuffs. The botanical provenance of 12 significant historical Chinese dye plants was achieved for the first time, and five cases of confusions in the naming of dyestuffs in historical records were clarified, for example, the mixed-up of hong hua (safflower) and fan hong hua (saffron). Reasons for the confusion of plant names and the level of classification were discussed.
Dyestuffs and dyeing methods uncovered from the first systematic study of primary sources of documented dye recipes and dyes on historical and archaeological textiles
Four important historical dye manuscripts were systematically examined, including Duoneng bishi (Various arts in everyday life) and Tiangong kaiwu (Chinese Technology in the Seventeenth Century, Fig. 3) of the Ming Dynasty, and Neiwufu quanzong dang’an, Zhiranju buce (Complete File of the Imperial Household, Volume of the Weaving and Dyeing Bureau) and Bu jing (The Cloth Classic) of the Qing Dynasty, respectively recording the dye recipes of 13, 27, 40 and 66 colours involving 14, 13, 11 and 18 dyes. The former two manuscripts are integrated works on various crafts published to the general public, while the latter two manuscripts are specialised books on textile handicrafts, mostly for internal circulation within the textile production institutes. Based on the examination of the reliabilities of these sources, the dyestuffs and dyeing methods recorded were compared and analysed.
Alongside the archival research, 216 dyed yarn samples from 63 pieces of provenanced historical and archaeological textiles from 11 collections and archaeological institutes in China, the UK and Ireland including The Palace Museum, The V&A Museum and The National Museum of Scotland, were collected and chemically analysed. Samples of 5 – 10 mm length of loose thread per colour of interest from the reverse side of the textiles were carefully selected and taken. By UHPLC-PDA analysis, the dye sources of up to 89 % historical samples were identified with confidence, and evidence of dyestuffs was detected in some archaeological samples, depending on the burial environments and the preservation state of the textiles.
Overall, a limited number amounting to nine dyestuffs were commonly used during this time period, namely safflower, sappanwood, indigo, Chinese cork tree, pagoda bud, acorn cup, turmeric, smoketree and gallnut (Fig. 4, from left to right, top to bottom). Uncommon dyestuffs including lac and cochineal identified in historical textiles may help provenance the production of the textiles. Several early synthetic dyes were identified alongside natural dyes in late-Qing textile samples, which promoted or confirmed the dating of the textiles, based on the dates when these dyestuffs were first synthesis and put into market. Dyestuffs were chosen to obtain various shades mainly according to the colour groups they belong to. Statistical analysis showed that with the development of dyeing techniques, better dyestuffs and dyeing methods were adopted, and colours were enriched by variations in the combination and quantity of different dyestuffs and mordants.
Further understanding of the textiles and dyeing handicraft in the social and global contexts
Knowledge about dyestuffs can promote the understanding of textiles in areas such as the determination of ownership, dating and provenancing. Take determining ownership as an example - in the Qing Dynasty, yellows were regulated as colours used especially by the imperial family: bright yellow was worn by emperors, apricot yellow by crown princes (later abandoned), golden yellow by princes, and women’s clothes were regulated accordingly. Dye recipes of the imperial weaving and dyeing bureau shows these yellows were obtained by different dyestuffs to show significant colour difference to differentiate statuses in the court. The detection of pagoda bud alone from the yellow ground samples of four pieces of dragon robes and a dragon badge, with comparison to the imperial dye recipes for the yellows, confirmed their original bright yellow colour (one of the dragon robes is presented in Fig. 1), even though the textiles were more or less faded. This thus confirmed that these five pieces belonged to emperors or court dowagers of the highest rank. This is also a piece of evidence that dyeing handicraft developed with the evolvement of colour decrees for textiles.
By examining Chinese dyeing in the global context, it was also concluded that dyestuffs specific and indigenous to China could help provenance Chinese textiles from textiles from other origins. Exchange in dyeing between China and Europe during the Ming and Qing Dynasties was limited in terms of dyeing with natural dyestuffs but the invention of synthetic dyestuffs in Europe and trade with China greatly changed the landscape of dyeing in China from the late 19th century.
Preservation of the dyed textiles
The results of accelerated light ageing study of reference dyed samples showed that among the common natural dyestuffs, safflower and turmeric are the most light-sensitive, and thus light exposure on textiles with these dyestuffs needs to be strictly limited to slow down fading. It is to be noted that almost all the red and pink samples analysed in this doctoral research involve safflower, and it is therefore highly likely that red and pink colours on Chinese textiles of the Ming and Qing Dynasties with unknown dye sources were dyed by safflower and thus are light sensitive.
Overall, this research built up the first complete picture of dyeing techniques in the Ming and Qing Dynasties by innovative methodologies and based on abundant primary sources, filling major gaps in textile history, colour history and plant history. For the excellence of this research, the researcher was selected by the China Scholarship Council for a prestigious National Excellent Self-Funded Students Scholarship.
The author would like to acknowledge the supervision of Dr Anita Quye and Professor Nick Pearce, and financial support from the Textile Conservation Foundation, the Swire Charitable Trust, the Sino-British Fellowship Trust, the Great Britain-China Educational Trust and the Sym Charitable Trust for this doctoral research.
The author would be delighted with further communication on relevant topics. Contact information: firstname.lastname@example.org
Jing Han gained a Bachelor degree and a Masters degree in conservation science from School of Archaeology and Museology, Peking University respectively in 2009 and 2012. She completed this doctoral research on Ming and Qing dyeing history at the Centre for Textile Conservation and Technical Art History, University of Glasgow early this year. Currently she is involved in short-term postdoctoral research and tea